<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="lib/vue.js"></script>
</head>
<body>
  <div id="root">
    <a @click="fn" href="http://baidu.com">1</a>
    <a @click.prevent="fn" href="http://baidu.com">2</a>

<!--    串联-->
    <a @click.prevent.once="fn" href="http://baidu.com">2</a>
  </div>
</body>
<script>
  const vm = new Vue({
    el: "#root",
    methods:{
      fn(){
        alert(111);
      }
    }
  });
</script>
</html>